Not only in electronic devices such as TV sets or personal computers but also in automobiles or industrial devices, there have been used a number electronic parts, major ones of which can be exemplified by connectors and sockets. Most of these connectors used are generally box-shaped to have a length of several centimeters and a section of about 1 cm.times.1 cm. As shown in FIG. 1, the connector and the socket are conducted by inserting the socket into the connector so that they function as the electronic part. Usually, the connector and the socket thus function as the integral part and are therefore demanded to be accurately connected. As means for this desire, the connector is provided with an erroneous insertion preventing slot, whereas the socket is provided with a bump (or a raised portion) to be snugly fitted in that erroneous insertion preventing slot (as shown in FIG. 1).
Thus, the bump of the socket is fitted in the erroneous insertion preventing slot of the connector. When the socket is to be inserted, there has frequently arisen a problem that a stress concentrates in the vicinity of the erroneous insertion preventing slot of the connector so that the erroneous insertion preventing slot is cracked or broken (as shown in FIG. 2 and FIG. 3).
The present invention has been conceived from the aforementioned point of view and has an object to provide a connector which is so shaped as to properly disperse a stress generated when a socket is inserted, thereby to prevent cracks or breakages effectively.